[morzh]

Brad

>>> without replacement caps just hanging out of the terminals.

Well, they would work but not quite as intended, as the very first 8nF cap would act almost as the three 3nF caps engaged.
Still not good.

The brown glue - I get it on Amazon. Just make sure your stick fits your gun.


Ron, Mike

Yeah I find "nF" more convenient. Does not require me to write as many zeroes.
Like 0.001uF i/o 1nF, or 0.01uF vs 10nF.
My CADs are flexible and do not dictate what prefixes can or cannot be used so I use them there also. Well, since I am the only one reading them anyways no one complains.

I think in the US the lack of the nF is for the same reason we use US imperial units in spatial measurements. (those I actually like).

[morzh]

So, recap/recarb has been finbished.

   


Now I have a question:

It seems that a resistor with the value of about 80 ohms has been placed between the  RF AMP plate and the rest of the circuitry (Cap #40, a 100pF and a band switch's contact). I cannot find the service bulletin mentioning that.
The soldering is clearly original factory one so it is not some repairman's "improvement".

   

[morzh]

I have not devoted much time to the chassis so far these two days, but at least I attached the power cord and tested the transformer with my Variac; it looks fine.
I thought to maybe try powering it up but I remembered I am lacking two tubes (forgot which ones) and I have not found/bought them yet.

[morzh]

I thought I did not have 78 tubes.
Also I realized one of the 78 tubes was replaced with a 77 one.
When I damaged one 78 in the beginning, I thought I did not have any in stock and now I even thought of buying some. Then I looked at my bench plastic bins, and I have a whole bin-full of them.
So I picked three that tested like new.

Also on the photo you could see a 77 tube's (the one right under the two IF cans) grid wire is outside the shell; I am sure it should be inside.

So I put all the tubes in, made sure it started rectifying at about 50VAC, and then went to 110VAC.
There was hum in the speaker and it reacted to the volume pot wiper being touched.
I could hear aerial noise, but rotating the tuning cap at where the local station is did not result in reception, so I will have to look at the RF circuit.
But so far no smoke and AF working is a good sign.


PS. Of course it works. I came down to see why there is no reception and then it occur to me to check the band switch posiition. Sur'nuff, it was on some SW band. Put in the BC position, the radio clearly receives the local station.

PPS. Putting the heat shield to the wire-wound resistor in the back proved to be a bit of a challenge. When taking that off I did not feel like taking the resistor out, so I bent a side. Putting it back was not possible without taking the resistor out, so I straightened the bent side, took the resistor out and then the insulating washer that is in between the holder and the resistor's end (probably to stress-relieve the ceramic) disintegrated, having been burnt over the years. And I do not have a fibre washer in the house. So I searched far and wide and found a fibre bushing which was exactly the right size and the internal diameter, so I saw off a piece to make a washer, and then spent some 15 minutes hand-sanding it to the right thickness. Eventually it went in. So the under-chassis is done.

I turned the speaker towards myself when playing (the cone facing the bench top obviously affects the sound) and was pleasantly surprise by a good clean base.

Now to alignment.

[morzh]

Does anyone know what grommets/bushings are used in the tuning cap support? From my measurements, the bushings should be 5/8" OD, 1/2" length and 0.25" ID, fitting 7/16" holes.

However it is inferred and the measurement does not tell me if the top and bottom parts are of equal thickness etc, and whether I am correct.

Renovated Radios, if they still ship, have T03 support, of which I would need 2 per hole, so 6 total. Put together they would make for the measurements above. I would prefer one part instead of the two.


Where else I could find them? I used Lowe's but recently they stopped replenishing the stock of their "Hard-to-find" bushings/grommets.
I am trying Hillman - It is their products that Lowe's sells..

[Simon Wa3uay]

I wish I knew, as I will also need them on the model 90 I'm working on....

edit: Don Patterson is mentioned as a source of Tuning Cap Grommets in the Philco Library; is he still a viable source? I don't see a web site or anything....
-Simon

[morzh]

Simon

I successfully used Hillman's grommets from Lowe's for 90 and all other radios, but these are larger.
The grommets from RR would fit but they are shorter than the 1/2" the metal bushing is.
Of course I could pad them with rubber washers as I did before many times.

Well, maybe I will again go to Lowe's, see if they have some left.

[morzh]

Well, I went to the Renovated Radios again and re-browsed; a couple of Zenith tuner supports seemed to fit the task and I ordered 6 of each.
They are still shipping, and in fact I got the shipping notification literally 30 minutes since I had ordered. Maybe it will come before I leave Saturday for vacation.

Simon,

http://renovatedradios.com/productlist.p...ondary=120

T07 and T14 seems to fit. Worst case two 1/16" rubber washers will let it compress a bit more.

[morzh]

the grommets came from RR; I used the symmetrical one; it is smaller and is exactly 1/2" thick; it took quite an effort to insert them, especially the one to the left of the switch at the front: very little space and a wirte bundle, and the fact it is on the left of the switch (not much space to use a tool held in my right hand) contributed to the difficulty. But eventually they all went in. After having tightened all three screws I was pleasantly surprised by the lack of wobble, despite little or no compression of the grommets - the grommets are quite a bit wider than the originals and provide good support when the tuning cap is attempted to be tilted.

BTW a good way to take off the solder of the screws (I unscrewed them with pliers) is to set your iron at 760 or so (regular soldering temp of 670-680 is a bit low for this), hold the screw with the pliers by the very end, heat it 'till the solder melts and simply shake it once downwards. Be careful not to do it over you feet - do it gently and over the bench. Once is enough.

No I have to re-assemble the volume pot, the tone ctl, re-solder the grounding mesh wires to the screws, blow the tuning cap (don't feel like taking it off and washing - it is clean but a tad dusty; a can of air should do) ad then align it.

And of course I have not had a chance to see the shadograph working, plus there is a light assembly.

PS. Reassembled everything, works fine.
Changed the bulb in the Shadograph; it works though the sector is really pushed to the right and the way it acts is almost as if there is a light sector that widens up instead of the dark one narrowing down when being tuned.
The band switch switches the band light indicators just fine.

[morzh]

The chassis aligned without much difficulty. Actually, it was very much aligned; the adjustments were very slight.

Now I have to fix a lamp of the band 4 that does not light up (and it is the one that the wrong size though I do not see how that would cause it), and then try to align the shadow meter to get the dark sector in the middle (when looking at it the sector i way to the right, so I only see the left edge of it).

[morzh]

The lamp of the Band 4 had the wire going to the switch broken. Easy.

I also look into the shadow meter, and decided all was good inside, so the arm holding the bulb got a bit of adjustment and now it works just fine.

After a while I started getting some raspy distortion that would come and go. I changed driver, a 42; it seems to have become less but once in a while a hint of it would still come.
Then I remembered that the 20-100-130 Ohm divider that creates the biases for the 1st AF and the driver (77 and 42) was in fact 21-170-200 or so, so I paralleled two resistors to make it 21-101-120, close enough to the original.
The radio seems to play clear for awhile but I have to run it for much longer to make sure this does not return, as I cannot quite explain it with the grid bias that is a bit less negative.

I guess it will have to wait after the vacation; I am going in three days.

[morzh]

Well, the radio as good as dome; I put the chassis inside with the new set of chassis supports and the new bumper, all courtesy of RR.
However I entirely forgot the radio had no bolts top tighten the chassis down, it only had the "shipping" corner brackets that keep it from sliding back.

So I need a set of 4 screws and nuts, otherwise the supports keep it too high and I cannot put the knobs back.

I plugged it in and listen to it awhile: the sound is great.
Once I have the bolts and put the knows back on, I will download a photo.

But for all intents and purposes, this restoration is done.

The radio Kirk gave me about 8 years ago or so is eventually taken care of.

[morzh]

1/4" x 1" lag bolts, cut to 3/4" did the job holding the chassis.

So the radio has been finished. It plays very well.
Will need one more power strip.

[Radioroslyn]

Did you find some that are 9tpi or go with standard 20tpi and retap the holes?

[morzh]

Terry


I think it is 20 tpi, that Lowes sells.
I did not retap. I think it is just a hole in metal sheet.
3 out if 4 worked fine. The 4th one does not go and hold well, but it did not have much effect.


Is 9 tpi what should be there?